Radio transmission of information traditionally involves the employment of electromagnetic waves or radio waves as a carrier. Where the carrier is transmitted as a sequence of fully duplicated wave cycles or wavelets, no information is considered to be transmissible. To convey information, historically, the carrier has superimposed on it a sequence of changes which can be detected at a receiving point or station. The changes imposed correspond with the information desired to be transmitted. A provision of such carrier changes is generally termed to be a “modulation”.
Where the amplitude of the carrier is changed in correspondence with information to be conveyed, the carrier is said to be amplitude modulated (AM). Correspondingly, where the frequency of the carrier is changed in accordance with information to be conveyed, either rarified or compressed wave cycles are developed and the carrier is said to be frequency modulated (FM), or in some applications it is considered to be phase modulated. Where the carrier is altered by interruption corresponding with information, it is said to be pulse modulated.
Currently, essentially all forms of the radio transmission of information are carried out with amplitude modulation, frequency modulation, pulse modulation or combinations of them. With all such forms of modulation, inefficiencies necessarily are present. For instance, a one KHz audio AM modulation of an R.F. carrier operating at one MHz will be at a carrier utilization ratio of 1:1000 and similar carrier utilization occurs with corresponding FM modulation. For all forms of currently employed carrier modulation, frequencies higher and lower than the frequency of the R.F. carrier are produced. Since they are distributed over a finite portion of the spectrum on each side of the carrier frequency, they are called side frequencies and are referred to collectively as sidebands. The sidebands contain all the message information and it has been considered that without them, no message can be transmitted. Sidebands, in effect, represent a distribution of power or energy from the carrier and their necessary development has lead to the allocation of frequencies in terms of bandwidths by government entities in allocating user permits within the radio spectrum. This necessarily limits the number of potential users for a given R.F. range of the spectrum.
Over the previous few decades, electronically derived information has taken the form of binary formatted datastreams. These datastreams are, for the most part, transmitted through telecommunication systems, i.e., wire. Binary industry communication in general, commenced with the networking of computer facilities in the mid 1960s, an early networking architecture being referred to as “Arpanet”. A short time later, Telenet, the first public packet-switched network, was introduced to commerce. As these networks grew, protocols for their use developed. For example, a coding protocol, ASCII (American Standard Code for Information Interchange) was introduced in 1964. Local Area Networks (LAN) proliferated during the 1970s, the oldest and most prominent, Ethernet, having been developed by Metcalfe in 1973. Under the Ethernet concept, each station of a local system connects by cable to a transceiver and these transceivers then are inter-linked. In 1983, the Institute of Electrical and Electronic Engineers (IEEE) promulgated Ethernet with some modifications, as the first standard protocol for local area networks. That protocol remains a standard for essentially all forms of database conveyance or exchange.
While binary datastream transmission by wire has improved substantially in terms of data transfer rates, that improvement has not been the case where transmission is by utilization of the R.F. spectrum. The transmission inefficiencies occasioned with the modulation of an R.F. carrier have remained to the extent that an efficient high-speed transmission of binary information utilizing an R.F. carrier persists as an elusive goal of investigators.